Temporal dithering

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I've tried asking this question on several forums and haven't gotten a clear answer. Maybe someone on here can help.

So temporal dithering or Frame Rate Control(FRC) is a technique where pixels are flashed between 2 different colors to simulate a 3rd color correct? Panels that are 6bit+frc or 8bit+frc utilize this technique correct? This technique can be bothersome for some. The solution would be to get a monitor that is either true 8bit or true 10bit correct?

Well here's the complicated part. I'm hearing graphics cards can use temporal dithering as well. So for example the AMD Radeon inside of a Xbox one or Playstation 4 I hear are enabling temporal dithering to ON by default ignoring even if the panel is true 8bit or 10bit. BTW can someone confirm if these gaming consoles are utilizing temporal dithering?

My question then is if the gpu is defaulting to temporal dithering to ON by default would this cause pixels to flash in the same manner that a display using FRC would? Or does dithering from the gpu differ from display FRC and does not cause the flashing or flickering.

Secondly I had a question about bit depth. If a source material is encoded at 8bit and displayed on a true 10bit display would the display/gpu dither the content up to 10bit or would it just display it as is at 8bit? Also the other way around if source material is 10bit and displayed on 8bit does it get dithered down to 8bit?and does this dithering cause flicker or flashing like FRC?

I'm in the market for a display that would not have flicker from temporal dithering. As in when a static image is displayed it is just that, static not dynamic. Is there a technology that won't display temporal dithering flicker or a certain cable you can use to avoid it. Is there a way to test if a GPU is utilizing temporal dithering? Only a high speed camera would capture it right?

Thanks for any and all help.

[huhn]

So temporal dithering or Frame Rate Control(FRC) is a technique where pixels are flashed between 2 different colors to simulate a 3rd color correct? Panels that are 6bit+frc or 8bit+frc utilize this technique correct? This technique can be bothersome for some. The solution would be to get a monitor that is either true 8bit or true 10bit correct?

are you sure this can be seen by anyone that is not pressing here eyes at the screen.

6bit FRC is visible but it is not flashing it is just noisy. the color "flicking" between in FRC is nearly the same color is very very close it like 255 and 256.
Well here's the complicated part. I'm hearing graphics cards can use temporal dithering as well. So for example the AMD Radeon inside of a Xbox one or Playstation 4 I hear are enabling temporal dithering to ON by default ignoring even if the panel is true 8bit or 10bit. BTW can someone confirm if these gaming consoles are utilizing temporal dithering?
as far as i know MAMD is using random dithering and you should be happy they are.
sending full range RGB should stop it from dithering altogether.
it can be disabled on the PC but that's a very bad idea.

and the panel has nothing todo with it. it is just needed when the image is processed.


Secondly I had a question about bit depth. If a source material is encoded at 8bit and displayed on a true 10bit display would the display/gpu dither the content up to 10bit or would it just display it as is at 8bit? Also the other way around if source material is 10bit and displayed on 8bit does it get dithered down to 8bit?and does this dithering cause flicker or flashing like FRC?

video are stored in YCbCr at least 99 % of them and your display devices works in RGB and YCbCr-> RGB conversation needs dithering or you will end up with banding.

I'm in the market for a display that would not have flicker from temporal dithering. As in when a static image is displayed it is just that, static not dynamic. Is there a technology that won't display temporal dithering flicker or a certain cable you can use to avoid it. Is there a way to test if a GPU is utilizing temporal dithering? Only a high speed camera would capture it right?

dither flickering is not a real issue on screens compared to backlight flickering which is a real deal and does flicker unlike dithering.

[Asmodian]

The GPU would never use temporal dithering, the random dithering you mention is spacial isn't it?

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are you sure this can be seen by anyone that is not pressing here eyes at the screen.

6bit FRC is visible but it is not flashing it is just noisy. the color "flicking" between in FRC is nearly the same color is very very close it like 255 and 256.

as far as i know MAMD is using random dithering and you should be happy they are.
sending full range RGB should stop it from dithering altogether.
it can be disabled on the PC but that's a very bad idea.

and the panel has nothing todo with it. it is just needed when the image is processed.



video are stored in YCbCr at least 99 % of them and your display devices works in RGB and YCbCr-> RGB conversation needs dithering or you will end up with banding.



dither flickering is not a real issue on screens compared to backlight flickering which is a real deal and does flicker unlike dithering.

Okay that makes sense. Only thing is you say dither flicker is not a real issue because you can't see it unless your up close to it. But PWM you can't see it at all even if you are close to it but people still have an issue with it right? So maybe some people do have a sensitivity to temporal dithering in particular if that makes any sense. I've heard of people who claim they have a sensitivity to temporal dithering disable it from Intel side using a program called ditherig.exe and also use a nvidia card which supposedly does not have temporal dithering on by default resolve their issues.

So the conversion that happens within cards for ycbr to RGB or other processing that occurs within graphics cards for bit depth does not create any sort of flicker correct? It is just FRC that can maybe even create some noise if that correct?

[huhn]

The GPU would never use temporal dithering, the random dithering you mention is spacial isn't it?

not sure what you mean with spacail.

Okay that makes sense. Only thing is you say dither flicker is not a real issue because you can't see it unless your up close to it. But PWM you can't see it at all even if you are close to it but people still have an issue with it right? So maybe some people do have a sensitivity to temporal dithering in particular if that makes any sense. I've heard of people who claim they have a sensitivity to temporal dithering disable it from Intel side using a program called ditherig.exe and also use a nvidia card which supposedly does not have temporal dithering on by default resolve their issues.

So the conversion that happens within cards for ycbr to RGB or other processing that occurs within graphics cards for bit depth does not create any sort of flicker correct? It is just FRC that can maybe even create some noise if that correct?

dithering doesn't flicker the flickering comes from PWM backlight which has nothing todo with dithering.

random dithering and FRC dithering can look like pixel are moving very slowly or i should say the noise is moving.
and no you can not really disable temporal dithering with "intel" the display is doing it.

noise that is very close to it is on every TV and display that plays back video media even if the display is not FRC.

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not sure what you mean with spacail.




dithering doesn't flicker the flickering comes from PWM backlight which has nothing todo with dithering.

random dithering and FRC dithering can look like pixel are moving very slowly or i should say the noise is moving.
and no you can not really disable temporal dithering with "intel" the display is doing it.

noise that is very close to it is on every TV and display that plays back video media even if the display is not FRC.

I think asmodian mean spatial dithering.

Specifically for Xbox one and Playstation 4 is there a way to test if they are doing temporal dithering?

Is there a display that might be better at covering up dithering noise? For example I know plasma dither heavy. Are some tech better at covering it up like true 8bit or 10bit IPS. Or maybe projector etc. Or maybe a cable like this one
https://arstechnica.com/gadgets/2017/09/theres-a-directional-120-hdmi-cable-that-actually-improves-your-picture-quality/

Thank you for the help.

[nevcairiel]

If dithering is temporal or spatial doesn't necessarily influence if the image changes from refresh to refresh. Temporal dithering just means that the dithering "error" is distributed over several frames, ie. what FRC does. Spatial dithering distributes the error within one frame (ie. Error Diffusion in madVR, for example).
Even spatial dithering can change from frame to frame, if you for example use fully random dithering which is re-generated randomly every frame.

[Link]

If dithering is temporal or spatial doesn't necessarily influence if the image changes from refresh to refresh. Temporal dithering just means that the dithering "error" is distributed over several frames, ie. what FRC does. Spatial dithering distributes the error within one frame (ie. Error Diffusion in madVR, for example).
Even spatial dithering can change from frame to frame, if you for example use fully random dithering which is re-generated randomly every frame.

Okay thank you for that info. I had I guess misinformed people telling me dithering causes this flashes and flickering in your face that is similar to PWM and causes issues. Or maybe i was misinterpreting. See this article and what he says about dithering. http://www.conradbiologic.com/articles/SubliminalFlickerI.html

[Asmodian]

That article talking about FRC when discussing dithering but seems overly worried about it. The other types of flickering they discuss is so much more significant, the total brightness changes due to FRC are so much smaller than a pulsed backlight, CRT, or the flickering caused by too much voltage drop during the LCD hold phase.

I think asmodian mean spatial dithering.

Ah yes, thank you. Spelling is not my strong suit. :o

If dithering is temporal or spatial doesn't necessarily influence if the image changes from refresh to refresh. Temporal dithering just means that the dithering "error" is distributed over several frames, ie. what FRC does. Spatial dithering distributes the error within one frame (ie. Error Diffusion in madVR, for example).
Even spatial dithering can change from frame to frame, if you for example use fully random dithering which is re-generated randomly every frame.

Very good point, I had forgotten that when bring up spatial dithering. Do we know if GPUs use a new dither pattern for every frame?

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That article talking about FRC when discussing dithering but seems overly worried about it. The other types of flickering they discuss is so much more significant, the total brightness changes due to FRC are so much smaller than a pulsed backlight, CRT, or the flickering caused by too much voltage drop during the LCD hold phase.

Okay so FRC dithering is a non issue right and as huhn said not exactly a flicker more like noise. When you say too much voltage drop during lcd hold phase, is that inversion? Is inversion flicker visible flicker or you can't see like PWM? Do modern lcd suffer from voltage drop flicker?

Also I think that website is quackery and outdated information because the guy wants to charge $120 an hour for advice lol.

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Had a question. Say if you have the xbox or ps4 hooked up to a true 10bit monitor that does not use FRC. Most games are encoded at 8bit. So will those 8bit games get dithered up by xbox one or ps4 because it will recognize that it hooked up to a 10bit display? If so can this create any flicker?

Also the xbox one give you the option to only select 8bit or not enable deep color. Given if you don't enable deep color on console will then the console send image in 8bit to the 10bit display? And will sending a 8bit to a true 10bit non FRC monitor just make it so that it displays in the same way a true 8bit would?

[huhn]

Okay so FRC dithering is a non issue right and as huhn said not exactly a flicker more like noise. When you say too much voltage drop during lcd hold phase, is that inversion? Is inversion flicker visible flicker or you can't see like PWM? Do modern lcd suffer from voltage drop flicker?

who knows there are a lot of LCD and PWM flickering is still a thing if not more than ever right now.

Had a question. Say if you have the xbox or ps4 hooked up to a true 10bit monitor that does not use FRC. Most games are encoded at 8bit. So will those 8bit games get dithered up by xbox one or ps4 because it will recognize that it hooked up to a 10bit display? If so can this create any flicker?

games are not encoded. they usually only support 8 bit output but 10 bit is possible too depends on the game. but if you send a limited range or YCbCr signal you can bet it get's dithered 2 times.

but really don't think to much about dithering. videos in games and even games it self have very similar noise just because they >can< your screen should not flicker because of dither.

to make it even better i hope you made sure your lightning in your room is DC so it doesn't flicker.

Also the xbox one give you the option to only select 8bit or not enable deep color. Given if you don't enable deep color on console will then the console send image in 8bit to the 10bit display? And will sending a 8bit to a true 10bit non FRC monitor just make it so that it displays in the same way a true 8bit would?

and that doesn't matter for a display if it has FRC it will nearly for sure always use it they do processing in the screens to that can't be disabled.

[Asmodian]

Okay so FRC dithering is a non issue right and as huhn said not exactly a flicker more like noise. When you say too much voltage drop during lcd hold phase, is that inversion? Is inversion flicker visible flicker or you can't see like PWM? Do modern lcd suffer from voltage drop flicker?

Today it seems to only be an issue with variable refresh rate displays when the refresh rate is too low, setting LCDs to 24 or 30 Hz will also cause it on some displays.

Edit:
It is very visible (it flickers at the frame rate) unlike PWM but PWM is the only flicker I would be concerned about. This is not inversion.

Also I think that website is quackery and outdated information because the guy wants to charge $120 an hour for advice lol.

I agree, some good, if old, information mixed in with a lot of quackery. :p

[Link]

who knows there are a lot of LCD and PWM flickering is still a thing if not more than ever right now.

are not encoded. they usually only support 8 bit output but 10 bit is possible too depends on the game. but if you send a limited range or YCbCr signal you can bet it get's dithered 2 times.

but really don't think to much about dithering. videos in games and even games it self have very similar noise just because they >can< your screen should not flicker because of dither.

When you say there's a lot of lcd out there are you trying to say there are a lot crappy lcd out there that they migjt flicker for various reasons. But if you have a decent to high end monitor that is pwm free no FRC dithering is not gonna cause some flicker right. Just noise.

So let's say someone hypothetically wants to remove all temporal dithering the only way to do it would be on PC side correct? How do you do that? You go into nvidia control panel and there's an option?

[huhn]

you can't make sure there is no dithering.
if it is temporal or not is a different story because any decent screen will dither and that always.

AMD supports a way with the reg to disable dithering but this will result in a desaster if the bit deep send to the GPU doesn't match or is lower than the GPU output bit deep.

[Link]

you can't make sure there is no dithering.
if it is temporal or not is a different story because any decent screen will dither and that always.

AMD supports a way with the reg to disable dithering but this will result in a desaster if the bit deep send to the GPU doesn't match or is lower than the GPU output bit deep.

Okay got it bottom line is dithering is not something to worry about right? Disabling would result in crazy banding right? Is there a way to like mask dithering? Like maybe a certain cable or video processing device?

[huhn]

no best you can do is not touching it.

[Link]

Some questions

If I have a true 10bit display, would non 10bit sources get dithered up by the graphics card? For example say I have a xbox one set up to display at 10bit to a 10bit display. Would the gpu in Xbox temporal dither up 8bit sources to 10bit? Or since the source is 8bit the gpu and display would only utilizie 8bpc and display as is like any other 8bit display would?

Or say if you have a nvidia 1080ti hooked up to a 10bit display, would 8bit sources get temporal dithered up or just display as is?

Thank you for any help.

[huhn]

like i said before video sources are not RGB so they need conversations so they need dithering.

[Link]

like i said before video sources are not RGB so they need conversations so they need dithering.

Sorry I should've made myself more clear. I know panel is rgb and video is ycbr so there is that conversion but that conversion is not temporal dithering right?

Aside from video if a 10bit display is hooked up to a 10bit gpu from what I understand almost all games are rgb 8bit. So will the gpu dither the game to 10bit or just display as is. If it dithers is it temporal? For nvidia 1080ti it wouldn't be right?

Is nvidia 1080ti true 10bit card or 8bit+2 dithering?

[huhn]

well then.
every decent screen is dithering no matter what the input it. it just dithers for it internal processing.

if it is temporal or not who knows. random dithering has the same effect as temporal.
and yet again dither has nothing to do with flicker...